Intrauterine insults can increase the risk of adverse birth outcomes, including miscarriage, prematurity, stillbirth and low birth weight. Mycotoxins are produced by molds that contaminate staple foods. One family of mycotoxins, aflatoxins (AF), has been widely studied and is known to cause liver cancer. Two other mycotoxins, fumonisin (FUM) and deoxynivalenol (DON) are often co-contaminants with AF in maize. All three mycotoxins have been shown to cross the placenta and may affect the fetus during critical periods of growth and development; however, none of these toxins or their combination has been rigorously studied with regard to pregnancy outcomes. The objective of this application is to characterize pregnancy exposure to multiple mycotoxins and its relation to birth outcomes in rural Zimbabwe. Our over-arching hypothesis is that AF exposure, alone or in combination with FUM and DON, is an important cause of adverse birth outcomes (poor fetal growth, miscarriage, stillbirth and preterm birth) globally. Our approach takes advantage of a large pregnancy cohort with outstanding field, lab and data management funded by the Bill & Melinda Gates Foundation (BMGF): the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial. Birth outcomes (miscarriage, stillbirth, prematurity, small-for-gestational age and stunted-for-gestational age) are already being measured, and we have strong evidence that mycotoxin exposures are prevalent and significant in this study population. The SHINE trial, an ongoing community-based trial of 4800 mother-infant pairs recruited during the first half of pregnancy in two rural districs of Zimbabwe. SHINE is a factorial cluster-randomized controlled trial investigating the independent and combined effects of improved water, sanitation and hygiene (WASH) and/or improved infant and young child feeding (IYCF) on stunting and anemia at 18 months of age. In this proposal, we leverage the existing SHINE infrastructure to assess mycotoxin exposure during pregnancy. Specific Aim 1 is to describe the prevalence and severity of multiple mycotoxin exposures in a large representative sample of pregnant women in rural Zimbabwe. Specific Aim 2 will characterize the relationship between maternal serum aflatoxin-albumin concentration during pregnancy and adverse birth outcomes [preterm birth, low birth weight (LBW), small-for-gestational age (SGA) and short-for-gestational age] in HIV-negative mothers Specific Aim 3 will explore the joint exposures of FUM, DON and AF in relation to risk of preterm birth. The proposed research will generate novel information about the burden of multiple mycotoxins (AF, FUM, DON) during pregnancy and the relative contribution of aflatoxin exposure to adverse birth outcomes. This evidence will provide foundations for future research exploring the potential mechanisms linking mycotoxin exposure to adverse birth outcomes and provide a rationale for the development and targeting of interventions to reduce mycotoxin exposure during pregnancy.